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    BME688 gas resistance stuck at one value

    BME688 gas resistance stuck at one value

    New Poster

    Like many other BME688 users, I've run into the issue where the gas resistance is stuck at a certain value with no response to stimuli over an extensive test duration. I am operating the chip in Forced Mode and able to stream all other variables (temp, humidity, pressure) normally except for the gas resistance. I have built up boards with four different BME688 chips and see the same behavior in all of them (although stuck at slighly different values).

    Here is some sample data where the gas resistance can be seen stuck at 12946861.

    Data: Temp (degC x1000), Pressure, Humidity (RH% x1000), Gas resistance, Sensor state

                                                                                   Gas resistance:

    <info> app: Top: 24856, 99695, 12607, 12946861, 0xB0
    <info> app: Top: 24858, 99699, 12559, 12946861, 0xB0
    <info> app: Top: 24853, 99700, 12525, 12946861, 0xB0
    <info> app: Top: 24813, 99691, 13013, 12946861, 0xB0
    <info> app: Top: 24828, 99699, 13028, 12946861, 0xB0

    I'm using the BME68x API with the exact same setup parameters as their forced mode example, so I am not sure why it is having problems. None of the previous forum posts I have seen so far offer a solution to this issue. Insight would be appreciated!

    1 REPLY 1

    Community Moderator
    Community Moderator

    Hi ndavis,

    Thanks for your inquiry.
    How long did you do the test when you run force mode example code?
    The new BME68x sensor requires 7 days to stabilize performance and half an hour to adapt to the new environment. It takes 15 minutes to stabilize the chip performance each time it is powered on.